Babe, you got Sole
Kate is another one of those people who doesn't easily flip her lid. But grammar is one of those things that can drive intelligent people crazy. I know this because I date Jeremy Griffin, who is both intelligent and crazy (which is why I like him so much).

So, editors are supposed to catch mistakes, right? Apparently not in Kate's textbooks.

Soul vs. sole.

Soul Cleansing
Shoe Sole
Everlasting Soul
Sole reason.

The only adjective form of soul is:
of, characteristic of, or for black Americans or their culture: soul newspapers.
You are a king by your own fireside, as much as any monarch in his throne.